Arena opponents are picked based on rating. The matchmaking system looks for opponents above or bellow the player's rating at equal increments until it finds a worthy opponent. Players may win or lose between 1 and 40 rating points at the end of a match. If the two opponents have similar ratings, they will win or lose approximately 20 points. If no opponent is found within 20 seconds the player is matched with an A.I. of equivalent skill level.

At the end of each match, players can see how well they've performed with each hero. The Damage column shows the total amount of damage including auto attacks, single target damage and area damage.

The healing column shows the total healing done, damage absorbed, damage that missed and any damage reduction. The Gladiator's Red ability for example provides a buff to friendly heroes that makes them take half damage. Each time the buff cuts incoming damage in half, the same amount is added as healing done by the Gladiator. This makes the score screen provide more accurate numbers and it makes it easier to figure out how well each hero performs.

The alive column shows how long each hero was alive during the match. Heroes are balanced to provide roughly the same amount of points if their damage and healing columns are added. It's important to know however that in arena damage increases by 50% with each minute that passes.

The combat log allows players to analyze what happened in a match second by second. The log shows the use of abilities, their effects, auto attacks and hero deaths.
To help players better understand the game, the ability icons can be clicked on to load more information about them.

In arena players are separated into geographical regions. They can see their own rank, victories, losses and rating as well as those of other players from the same region at any point during the season. Seasons last one week and reset on Sunday night for each region and start immediately afterwards. The A.I. is automatically awarded specific ranking stats based on its difficulty level however these do update whenever the A.I. wins or losses a match. The A.I. increases in difficulty every 100 rating between 1000 and 2000 rating points.

Recent matches shows activity from all regions. Players can see what others are using for hero compositions, their success, the map matches were played on, how long the matches lasted and several other pieces of information. Only the 20 most recent matches are displayed.

There are many rewards that players can obtain by playing Tome of Heroes and more are still being added. During a season, upon reaching 1500 or 2000 rating, players can upgrade the skins of their heroes to silver and gold quality. Players above 1750 and 2000 are also awarded a number of gems and coins. Players can also participate in the Daily Quests and if they complete the challenge they're awarded 1 coin.

While searching for an Arena match, if no appropriate opponent is found the player is matched with an A.I. These are designed to play the game similarly to how an opponent at that rating would play it. The difficulty of the A.I. increases with every 100 rating until 2000 rating. Matches versus the A.I. count the same way that matches versus a human opponent would and ranking stats are updated for both the player and the A.I.

Gems are an in-game currency that can be used to play additional consecutive games after while the first 5 free ones re-charge. You can also wait 30 minutes for each free game to charge back. During a season, if you reach 1500 rating you can use gems to upgrade the skins of your heroes to Silver quality and at 2000 rating to Gold quality. Gems can be purchased at the in-game shop or obtained for free from in-game activities:

Registering your account will award you 100 gems.

Completing quests will award you between 10 and 80 gems for each completed quest.